There exists today massive national and international communication switch networks whereby an end user connected to one node can communicate to an end user, or to a particular internodal facility. These nodes or frames can be in the same office, across town, across a continent, around the world, and perhaps even in space.
These networks are constructed having at least one rearrangeable cross-connect field at each node. The cross-connect field operates under control of instructions from a network controller and serves to interconnect a plurality of end users to the internetwork communication links. The interconnections through the cross-connect field are semipermanent in nature and can last for a single communication connection or can last for a period of time which may span several such connections.
End users can be permanently assigned certain link capacity on a cross-connect field or can share the capacity with other users of the same cross-connect field. This shared usage is called pooling. It is now common place for any one user to have facilities permanently assigned and to have additional periodic facility capacity by using the shared facility pool.
Within each internetwork link there are channels which can be used to establish communication connections. For certain types of communications more than one channel is necessary in order to establish the desired bandwidth capability. Usually, these channels must be contiguous in order to create the necessary bandwidth for a given communication connection. There are several such facilities interconnecting each network node and from any particular end user to any remote end user (or other communication facility, such as a computer) there could be many different links or paths. Thus, for a connection from one end user at a given node to another end user at a different network node there would be a choice of routes that could be established. Some of these routes are more cost effective than others. Presently, when an end user who has access to a shared pool of facilities wishes to become connected to the pool, an attendant must communicate with the network manager and request the establishment of the proper connection. The network manager then assigns the proper routing (including the facilities and channels) to the end user for a particular period of time and establishes the connections required to affect the end to end circuit.
This arrangement is both time consuming and very inefficient from an attendant's point of view. In some situations, the use of pooled internodal facilities for short periods of time is not practical if an attendant must become involved. This is so for many reasons, one of which is the fact that often the desired use of the pooled facilities is for a short duration for the purpose of data transfer, which usually is scheduled to occur after normal hours and at other inconvenient times. Also, since a network serves many such end users, and since each end user has a number of different connection requests, the delay in central administration can become prohibitive.
In any such system, billing becomes a major concern. Each customer, or user, of the system desires to be billed for the actual time they are using the network. The users, however, have scheduled time through the network and in order to achieve the lowest possible costs, it is to their advantage to schedule this time early so that the best (in terms of cost) routes are available and not booked by some other customer.
This situation, then, could lead to a practice that would make it advantageous for users to book prospective time early to assure availability and then, at the last minute, cancel the reservation if the time were not actually going to be utilized by the user. This would result in lost revenue to the network provider as well as inconvenience to other users who could not schedule their time for the lowest cost routing.
Thus, a need exists in the art for a system in which a controller central to a plurality of network nodes can establish, on a timed basis, cross-connections at the various nodes so that users sharing the internetwork facilities can have bandwidth established between any end points of the network for periods of time under control of the users and in which billing can be printed dependent upon usage and scheduled usage.
A further need exists in the art for such a system which allows each end user sharing a common pooled set of communication facilities to schedule a series of timed connections through the entire network, from end point to end point, with each connection routing occurring at a particular given time. Such a system must also have the capability of determining the least cost prospective routing, verifying that the user in fact has allowance for using the requested facilities, for establishing the routing only for the proper period of time, and of supplying an audit trail for billing purposes.